2 * Copyright (C) STRATO AG 2012. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
18 #include <linux/sched.h>
19 #include <linux/bio.h>
20 #include <linux/slab.h>
21 #include <linux/buffer_head.h>
22 #include <linux/blkdev.h>
23 #include <linux/random.h>
24 #include <linux/iocontext.h>
25 #include <linux/capability.h>
26 #include <linux/kthread.h>
27 #include <linux/math64.h>
28 #include <asm/div64.h>
30 #include "extent_map.h"
32 #include "transaction.h"
33 #include "print-tree.h"
35 #include "async-thread.h"
36 #include "check-integrity.h"
37 #include "rcu-string.h"
38 #include "dev-replace.h"
40 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
42 static void btrfs_dev_replace_update_device_in_mapping_tree(
43 struct btrfs_fs_info *fs_info,
44 struct btrfs_device *srcdev,
45 struct btrfs_device *tgtdev);
46 static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid,
48 struct btrfs_device **device);
49 static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info);
50 static int btrfs_dev_replace_kthread(void *data);
51 static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info);
54 int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info)
57 struct btrfs_root *dev_root = fs_info->dev_root;
58 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
59 struct extent_buffer *eb;
62 struct btrfs_path *path = NULL;
64 struct btrfs_dev_replace_item *ptr;
67 path = btrfs_alloc_path();
74 key.type = BTRFS_DEV_REPLACE_KEY;
76 ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
78 no_valid_dev_replace_entry_found:
80 dev_replace->replace_state =
81 BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED;
82 dev_replace->cont_reading_from_srcdev_mode =
83 BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS;
84 dev_replace->replace_state = 0;
85 dev_replace->time_started = 0;
86 dev_replace->time_stopped = 0;
87 atomic64_set(&dev_replace->num_write_errors, 0);
88 atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
89 dev_replace->cursor_left = 0;
90 dev_replace->committed_cursor_left = 0;
91 dev_replace->cursor_left_last_write_of_item = 0;
92 dev_replace->cursor_right = 0;
93 dev_replace->srcdev = NULL;
94 dev_replace->tgtdev = NULL;
95 dev_replace->is_valid = 0;
96 dev_replace->item_needs_writeback = 0;
99 slot = path->slots[0];
101 item_size = btrfs_item_size_nr(eb, slot);
102 ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item);
104 if (item_size != sizeof(struct btrfs_dev_replace_item)) {
106 "dev_replace entry found has unexpected size, ignore entry");
107 goto no_valid_dev_replace_entry_found;
110 src_devid = btrfs_dev_replace_src_devid(eb, ptr);
111 dev_replace->cont_reading_from_srcdev_mode =
112 btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr);
113 dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr);
114 dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr);
115 dev_replace->time_stopped =
116 btrfs_dev_replace_time_stopped(eb, ptr);
117 atomic64_set(&dev_replace->num_write_errors,
118 btrfs_dev_replace_num_write_errors(eb, ptr));
119 atomic64_set(&dev_replace->num_uncorrectable_read_errors,
120 btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr));
121 dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr);
122 dev_replace->committed_cursor_left = dev_replace->cursor_left;
123 dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left;
124 dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr);
125 dev_replace->is_valid = 1;
127 dev_replace->item_needs_writeback = 0;
128 switch (dev_replace->replace_state) {
129 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
130 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
131 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
132 dev_replace->srcdev = NULL;
133 dev_replace->tgtdev = NULL;
135 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
136 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
137 dev_replace->srcdev = btrfs_find_device(fs_info, src_devid,
139 dev_replace->tgtdev = btrfs_find_device(fs_info,
140 BTRFS_DEV_REPLACE_DEVID,
143 * allow 'btrfs dev replace_cancel' if src/tgt device is
146 if (!dev_replace->srcdev &&
147 !btrfs_test_opt(dev_root, DEGRADED)) {
150 "cannot mount because device replace operation is ongoing and");
152 "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?",
155 if (!dev_replace->tgtdev &&
156 !btrfs_test_opt(dev_root, DEGRADED)) {
159 "cannot mount because device replace operation is ongoing and");
161 "tgtdev (devid %llu) is missing, need to run 'btrfs dev scan'?",
162 BTRFS_DEV_REPLACE_DEVID);
164 if (dev_replace->tgtdev) {
165 if (dev_replace->srcdev) {
166 dev_replace->tgtdev->total_bytes =
167 dev_replace->srcdev->total_bytes;
168 dev_replace->tgtdev->disk_total_bytes =
169 dev_replace->srcdev->disk_total_bytes;
170 dev_replace->tgtdev->bytes_used =
171 dev_replace->srcdev->bytes_used;
173 dev_replace->tgtdev->is_tgtdev_for_dev_replace = 1;
174 btrfs_init_dev_replace_tgtdev_for_resume(fs_info,
175 dev_replace->tgtdev);
182 btrfs_free_path(path);
187 * called from commit_transaction. Writes changed device replace state to
190 int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
191 struct btrfs_fs_info *fs_info)
194 struct btrfs_root *dev_root = fs_info->dev_root;
195 struct btrfs_path *path;
196 struct btrfs_key key;
197 struct extent_buffer *eb;
198 struct btrfs_dev_replace_item *ptr;
199 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
201 btrfs_dev_replace_lock(dev_replace);
202 if (!dev_replace->is_valid ||
203 !dev_replace->item_needs_writeback) {
204 btrfs_dev_replace_unlock(dev_replace);
207 btrfs_dev_replace_unlock(dev_replace);
210 key.type = BTRFS_DEV_REPLACE_KEY;
213 path = btrfs_alloc_path();
218 ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
220 btrfs_warn(fs_info, "error %d while searching for dev_replace item!",
226 btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) {
228 * need to delete old one and insert a new one.
229 * Since no attempt is made to recover any old state, if the
230 * dev_replace state is 'running', the data on the target
232 * It would be possible to recover the state: just make sure
233 * that the beginning of the item is never changed and always
234 * contains all the essential information. Then read this
235 * minimal set of information and use it as a base for the
238 ret = btrfs_del_item(trans, dev_root, path);
240 btrfs_warn(fs_info, "delete too small dev_replace item failed %d!",
248 /* need to insert a new item */
249 btrfs_release_path(path);
250 ret = btrfs_insert_empty_item(trans, dev_root, path,
253 btrfs_warn(fs_info, "insert dev_replace item failed %d!",
260 ptr = btrfs_item_ptr(eb, path->slots[0],
261 struct btrfs_dev_replace_item);
263 btrfs_dev_replace_lock(dev_replace);
264 if (dev_replace->srcdev)
265 btrfs_set_dev_replace_src_devid(eb, ptr,
266 dev_replace->srcdev->devid);
268 btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1);
269 btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr,
270 dev_replace->cont_reading_from_srcdev_mode);
271 btrfs_set_dev_replace_replace_state(eb, ptr,
272 dev_replace->replace_state);
273 btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started);
274 btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped);
275 btrfs_set_dev_replace_num_write_errors(eb, ptr,
276 atomic64_read(&dev_replace->num_write_errors));
277 btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr,
278 atomic64_read(&dev_replace->num_uncorrectable_read_errors));
279 dev_replace->cursor_left_last_write_of_item =
280 dev_replace->cursor_left;
281 btrfs_set_dev_replace_cursor_left(eb, ptr,
282 dev_replace->cursor_left_last_write_of_item);
283 btrfs_set_dev_replace_cursor_right(eb, ptr,
284 dev_replace->cursor_right);
285 dev_replace->item_needs_writeback = 0;
286 btrfs_dev_replace_unlock(dev_replace);
288 btrfs_mark_buffer_dirty(eb);
291 btrfs_free_path(path);
296 void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info)
298 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
300 dev_replace->committed_cursor_left =
301 dev_replace->cursor_left_last_write_of_item;
304 int btrfs_dev_replace_start(struct btrfs_root *root,
305 struct btrfs_ioctl_dev_replace_args *args)
307 struct btrfs_trans_handle *trans;
308 struct btrfs_fs_info *fs_info = root->fs_info;
309 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
311 struct btrfs_device *tgt_device = NULL;
312 struct btrfs_device *src_device = NULL;
314 if (btrfs_fs_incompat(fs_info, RAID56)) {
315 btrfs_warn(fs_info, "dev_replace cannot yet handle RAID5/RAID6");
319 switch (args->start.cont_reading_from_srcdev_mode) {
320 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS:
321 case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID:
327 if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') ||
328 args->start.tgtdev_name[0] == '\0')
331 mutex_lock(&fs_info->volume_mutex);
332 ret = btrfs_init_dev_replace_tgtdev(root, args->start.tgtdev_name,
335 btrfs_err(fs_info, "target device %s is invalid!",
336 args->start.tgtdev_name);
337 mutex_unlock(&fs_info->volume_mutex);
341 ret = btrfs_dev_replace_find_srcdev(root, args->start.srcdevid,
342 args->start.srcdev_name,
344 mutex_unlock(&fs_info->volume_mutex);
350 if (tgt_device->total_bytes < src_device->total_bytes) {
351 btrfs_err(fs_info, "target device is smaller than source device!");
356 btrfs_dev_replace_lock(dev_replace);
357 switch (dev_replace->replace_state) {
358 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
359 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
360 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
362 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
363 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
364 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
368 dev_replace->cont_reading_from_srcdev_mode =
369 args->start.cont_reading_from_srcdev_mode;
370 WARN_ON(!src_device);
371 dev_replace->srcdev = src_device;
372 WARN_ON(!tgt_device);
373 dev_replace->tgtdev = tgt_device;
375 printk_in_rcu(KERN_INFO
376 "BTRFS: dev_replace from %s (devid %llu) to %s started\n",
377 src_device->missing ? "<missing disk>" :
378 rcu_str_deref(src_device->name),
380 rcu_str_deref(tgt_device->name));
382 tgt_device->total_bytes = src_device->total_bytes;
383 tgt_device->disk_total_bytes = src_device->disk_total_bytes;
384 tgt_device->bytes_used = src_device->bytes_used;
387 * from now on, the writes to the srcdev are all duplicated to
388 * go to the tgtdev as well (refer to btrfs_map_block()).
390 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
391 dev_replace->time_started = get_seconds();
392 dev_replace->cursor_left = 0;
393 dev_replace->committed_cursor_left = 0;
394 dev_replace->cursor_left_last_write_of_item = 0;
395 dev_replace->cursor_right = 0;
396 dev_replace->is_valid = 1;
397 dev_replace->item_needs_writeback = 1;
398 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
399 btrfs_dev_replace_unlock(dev_replace);
401 btrfs_wait_ordered_roots(root->fs_info, -1);
403 /* force writing the updated state information to disk */
404 trans = btrfs_start_transaction(root, 0);
406 ret = PTR_ERR(trans);
407 btrfs_dev_replace_lock(dev_replace);
411 ret = btrfs_commit_transaction(trans, root);
414 /* the disk copy procedure reuses the scrub code */
415 ret = btrfs_scrub_dev(fs_info, src_device->devid, 0,
416 src_device->total_bytes,
417 &dev_replace->scrub_progress, 0, 1);
419 ret = btrfs_dev_replace_finishing(root->fs_info, ret);
425 dev_replace->srcdev = NULL;
426 dev_replace->tgtdev = NULL;
427 btrfs_dev_replace_unlock(dev_replace);
430 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
435 * blocked until all flighting bios are finished.
437 static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info)
442 set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
444 prepare_to_wait(&fs_info->replace_wait, &wait,
445 TASK_UNINTERRUPTIBLE);
446 writers = percpu_counter_sum(&fs_info->bio_counter);
449 finish_wait(&fs_info->replace_wait, &wait);
454 * we have removed target device, it is safe to allow new bios request.
456 static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info)
458 clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state);
459 if (waitqueue_active(&fs_info->replace_wait))
460 wake_up(&fs_info->replace_wait);
463 static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
466 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
467 struct btrfs_device *tgt_device;
468 struct btrfs_device *src_device;
469 struct btrfs_root *root = fs_info->tree_root;
470 u8 uuid_tmp[BTRFS_UUID_SIZE];
471 struct btrfs_trans_handle *trans;
474 /* don't allow cancel or unmount to disturb the finishing procedure */
475 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
477 btrfs_dev_replace_lock(dev_replace);
478 /* was the operation canceled, or is it finished? */
479 if (dev_replace->replace_state !=
480 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) {
481 btrfs_dev_replace_unlock(dev_replace);
482 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
486 tgt_device = dev_replace->tgtdev;
487 src_device = dev_replace->srcdev;
488 btrfs_dev_replace_unlock(dev_replace);
491 * flush all outstanding I/O and inode extent mappings before the
492 * copy operation is declared as being finished
494 ret = btrfs_start_delalloc_roots(root->fs_info, 0);
496 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
499 btrfs_wait_ordered_roots(root->fs_info, -1);
501 trans = btrfs_start_transaction(root, 0);
503 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
504 return PTR_ERR(trans);
506 ret = btrfs_commit_transaction(trans, root);
509 /* keep away write_all_supers() during the finishing procedure */
510 mutex_lock(&root->fs_info->chunk_mutex);
511 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
512 btrfs_dev_replace_lock(dev_replace);
513 dev_replace->replace_state =
514 scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED
515 : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED;
516 dev_replace->tgtdev = NULL;
517 dev_replace->srcdev = NULL;
518 dev_replace->time_stopped = get_seconds();
519 dev_replace->item_needs_writeback = 1;
521 /* replace old device with new one in mapping tree */
523 btrfs_dev_replace_update_device_in_mapping_tree(fs_info,
527 printk_in_rcu(KERN_ERR
528 "BTRFS: btrfs_scrub_dev(%s, %llu, %s) failed %d\n",
529 src_device->missing ? "<missing disk>" :
530 rcu_str_deref(src_device->name),
532 rcu_str_deref(tgt_device->name), scrub_ret);
533 btrfs_dev_replace_unlock(dev_replace);
534 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
535 mutex_unlock(&root->fs_info->chunk_mutex);
537 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
538 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
543 printk_in_rcu(KERN_INFO
544 "BTRFS: dev_replace from %s (devid %llu) to %s) finished\n",
545 src_device->missing ? "<missing disk>" :
546 rcu_str_deref(src_device->name),
548 rcu_str_deref(tgt_device->name));
549 tgt_device->is_tgtdev_for_dev_replace = 0;
550 tgt_device->devid = src_device->devid;
551 src_device->devid = BTRFS_DEV_REPLACE_DEVID;
552 tgt_device->bytes_used = src_device->bytes_used;
553 memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp));
554 memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid));
555 memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid));
556 tgt_device->total_bytes = src_device->total_bytes;
557 tgt_device->disk_total_bytes = src_device->disk_total_bytes;
558 tgt_device->bytes_used = src_device->bytes_used;
559 if (fs_info->sb->s_bdev == src_device->bdev)
560 fs_info->sb->s_bdev = tgt_device->bdev;
561 if (fs_info->fs_devices->latest_bdev == src_device->bdev)
562 fs_info->fs_devices->latest_bdev = tgt_device->bdev;
563 list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
565 btrfs_rm_dev_replace_blocked(fs_info);
567 btrfs_rm_dev_replace_srcdev(fs_info, src_device);
569 btrfs_rm_dev_replace_unblocked(fs_info);
572 * this is again a consistent state where no dev_replace procedure
573 * is running, the target device is part of the filesystem, the
574 * source device is not part of the filesystem anymore and its 1st
575 * superblock is scratched out so that it is no longer marked to
576 * belong to this filesystem.
578 btrfs_dev_replace_unlock(dev_replace);
579 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
580 mutex_unlock(&root->fs_info->chunk_mutex);
582 /* write back the superblocks */
583 trans = btrfs_start_transaction(root, 0);
585 btrfs_commit_transaction(trans, root);
587 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
592 static void btrfs_dev_replace_update_device_in_mapping_tree(
593 struct btrfs_fs_info *fs_info,
594 struct btrfs_device *srcdev,
595 struct btrfs_device *tgtdev)
597 struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree;
598 struct extent_map *em;
599 struct map_lookup *map;
603 write_lock(&em_tree->lock);
605 em = lookup_extent_mapping(em_tree, start, (u64)-1);
608 map = (struct map_lookup *)em->bdev;
609 for (i = 0; i < map->num_stripes; i++)
610 if (srcdev == map->stripes[i].dev)
611 map->stripes[i].dev = tgtdev;
612 start = em->start + em->len;
615 write_unlock(&em_tree->lock);
618 static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid,
620 struct btrfs_device **device)
626 *device = btrfs_find_device(root->fs_info, srcdevid, NULL,
631 ret = btrfs_find_device_missing_or_by_path(root, srcdev_name,
637 void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
638 struct btrfs_ioctl_dev_replace_args *args)
640 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
642 btrfs_dev_replace_lock(dev_replace);
643 /* even if !dev_replace_is_valid, the values are good enough for
644 * the replace_status ioctl */
645 args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
646 args->status.replace_state = dev_replace->replace_state;
647 args->status.time_started = dev_replace->time_started;
648 args->status.time_stopped = dev_replace->time_stopped;
649 args->status.num_write_errors =
650 atomic64_read(&dev_replace->num_write_errors);
651 args->status.num_uncorrectable_read_errors =
652 atomic64_read(&dev_replace->num_uncorrectable_read_errors);
653 switch (dev_replace->replace_state) {
654 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
655 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
656 args->status.progress_1000 = 0;
658 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
659 args->status.progress_1000 = 1000;
661 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
662 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
663 args->status.progress_1000 = div64_u64(dev_replace->cursor_left,
664 div64_u64(dev_replace->srcdev->total_bytes, 1000));
667 btrfs_dev_replace_unlock(dev_replace);
670 int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info,
671 struct btrfs_ioctl_dev_replace_args *args)
673 args->result = __btrfs_dev_replace_cancel(fs_info);
677 static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
679 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
680 struct btrfs_device *tgt_device = NULL;
681 struct btrfs_trans_handle *trans;
682 struct btrfs_root *root = fs_info->tree_root;
686 if (fs_info->sb->s_flags & MS_RDONLY)
689 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
690 btrfs_dev_replace_lock(dev_replace);
691 switch (dev_replace->replace_state) {
692 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
693 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
694 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
695 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED;
696 btrfs_dev_replace_unlock(dev_replace);
698 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
699 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
700 result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
701 tgt_device = dev_replace->tgtdev;
702 dev_replace->tgtdev = NULL;
703 dev_replace->srcdev = NULL;
706 dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED;
707 dev_replace->time_stopped = get_seconds();
708 dev_replace->item_needs_writeback = 1;
709 btrfs_dev_replace_unlock(dev_replace);
710 btrfs_scrub_cancel(fs_info);
712 trans = btrfs_start_transaction(root, 0);
714 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
715 return PTR_ERR(trans);
717 ret = btrfs_commit_transaction(trans, root);
720 btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
723 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
727 void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info)
729 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
731 mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
732 btrfs_dev_replace_lock(dev_replace);
733 switch (dev_replace->replace_state) {
734 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
735 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
736 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
737 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
739 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
740 dev_replace->replace_state =
741 BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED;
742 dev_replace->time_stopped = get_seconds();
743 dev_replace->item_needs_writeback = 1;
744 btrfs_info(fs_info, "suspending dev_replace for unmount");
748 btrfs_dev_replace_unlock(dev_replace);
749 mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
752 /* resume dev_replace procedure that was interrupted by unmount */
753 int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
755 struct task_struct *task;
756 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
758 btrfs_dev_replace_lock(dev_replace);
759 switch (dev_replace->replace_state) {
760 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
761 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
762 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
763 btrfs_dev_replace_unlock(dev_replace);
765 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
767 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
768 dev_replace->replace_state =
769 BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED;
772 if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) {
773 btrfs_info(fs_info, "cannot continue dev_replace, tgtdev is missing");
775 "you may cancel the operation after 'mount -o degraded'");
776 btrfs_dev_replace_unlock(dev_replace);
779 btrfs_dev_replace_unlock(dev_replace);
782 &fs_info->mutually_exclusive_operation_running, 1));
783 task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl");
784 return PTR_ERR_OR_ZERO(task);
787 static int btrfs_dev_replace_kthread(void *data)
789 struct btrfs_fs_info *fs_info = data;
790 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
791 struct btrfs_ioctl_dev_replace_args *status_args;
794 status_args = kzalloc(sizeof(*status_args), GFP_NOFS);
796 btrfs_dev_replace_status(fs_info, status_args);
797 progress = status_args->status.progress_1000;
799 do_div(progress, 10);
800 printk_in_rcu(KERN_INFO
801 "BTRFS: continuing dev_replace from %s (devid %llu) to %s @%u%%\n",
802 dev_replace->srcdev->missing ? "<missing disk>" :
803 rcu_str_deref(dev_replace->srcdev->name),
804 dev_replace->srcdev->devid,
805 dev_replace->tgtdev ?
806 rcu_str_deref(dev_replace->tgtdev->name) :
807 "<missing target disk>",
808 (unsigned int)progress);
810 btrfs_dev_replace_continue_on_mount(fs_info);
811 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
816 static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info)
818 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
821 ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid,
822 dev_replace->committed_cursor_left,
823 dev_replace->srcdev->total_bytes,
824 &dev_replace->scrub_progress, 0, 1);
825 ret = btrfs_dev_replace_finishing(fs_info, ret);
830 int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace)
832 if (!dev_replace->is_valid)
835 switch (dev_replace->replace_state) {
836 case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
837 case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
838 case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
840 case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
841 case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
843 * return true even if tgtdev is missing (this is
844 * something that can happen if the dev_replace
845 * procedure is suspended by an umount and then
846 * the tgtdev is missing (or "btrfs dev scan") was
847 * not called and the the filesystem is remounted
848 * in degraded state. This does not stop the
849 * dev_replace procedure. It needs to be canceled
850 * manually if the cancelation is wanted.
857 void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace)
859 /* the beginning is just an optimization for the typical case */
860 if (atomic_read(&dev_replace->nesting_level) == 0) {
862 /* this is not a nested case where the same thread
863 * is trying to acqurire the same lock twice */
864 mutex_lock(&dev_replace->lock);
865 mutex_lock(&dev_replace->lock_management_lock);
866 dev_replace->lock_owner = current->pid;
867 atomic_inc(&dev_replace->nesting_level);
868 mutex_unlock(&dev_replace->lock_management_lock);
872 mutex_lock(&dev_replace->lock_management_lock);
873 if (atomic_read(&dev_replace->nesting_level) > 0 &&
874 dev_replace->lock_owner == current->pid) {
875 WARN_ON(!mutex_is_locked(&dev_replace->lock));
876 atomic_inc(&dev_replace->nesting_level);
877 mutex_unlock(&dev_replace->lock_management_lock);
881 mutex_unlock(&dev_replace->lock_management_lock);
885 void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace)
887 WARN_ON(!mutex_is_locked(&dev_replace->lock));
888 mutex_lock(&dev_replace->lock_management_lock);
889 WARN_ON(atomic_read(&dev_replace->nesting_level) < 1);
890 WARN_ON(dev_replace->lock_owner != current->pid);
891 atomic_dec(&dev_replace->nesting_level);
892 if (atomic_read(&dev_replace->nesting_level) == 0) {
893 dev_replace->lock_owner = 0;
894 mutex_unlock(&dev_replace->lock_management_lock);
895 mutex_unlock(&dev_replace->lock);
897 mutex_unlock(&dev_replace->lock_management_lock);
901 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info)
903 percpu_counter_inc(&fs_info->bio_counter);
906 void btrfs_bio_counter_dec(struct btrfs_fs_info *fs_info)
908 percpu_counter_dec(&fs_info->bio_counter);
910 if (waitqueue_active(&fs_info->replace_wait))
911 wake_up(&fs_info->replace_wait);
914 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info)
918 percpu_counter_inc(&fs_info->bio_counter);
919 if (test_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state)) {
920 btrfs_bio_counter_dec(fs_info);
921 wait_event(fs_info->replace_wait,
922 !test_bit(BTRFS_FS_STATE_DEV_REPLACING,
923 &fs_info->fs_state));